This invention relates to the field of treating benign prostatic hyperplasia and more particularly to the field of treating benign prostatic hyperplasia with laser energy.
Open surgery and transurethral resection are increasingly reliable and safe procedures for treating benign prostatic hyperplasia (BPH). The trend towards minimally invasive modes of therapy, however, can also be observed with respect to BPH. One reason is that as life expectancy grows, there is a greater number of aged patients who reach the stage where they require treatment, some of them suffering from BPH in addition to other conditions. Secondly, a large number of patients are simply afraid of surgical intervention and the possibility of complications. This is proven not only by the widespread use of phytopharmacological preparations, but also by the fact that new therapeutic approaches tend to become quickly popular, for example hyperthermia.
The current literature reports on a multitude of rediscovered and novel treatment concepts, which include various pharmacological methods, balloon dilatation, intraprostatic stents, focussed ultrasound therapy and cryosurgery, as well as different systems of hyperthermia and thermotherapy, where microwaves, for example, are applied transrectally or transurethrally.
Several work groups have been working with transurethral laser applications. Interstitial application, although arguably a logical next step, has so far been problematic: the customarily used bare fibers or contact tips led to a high concentration of heat, which resulted in uncontrollable carbonization, a process that absorbs laser rays and consequently prevents deep coagulation of the tissues.
It is known that an Nd:YAG laser (such as the Medilas 4060N fiberTome.TM., MBB Medizintechnik GmbH, Munich, Germany and Sharplan 3000 laser from Laser Industries Ltd., Tel Aviv, Israel) produces deep tissue coagulation in a minimally invasive manner, produces favorable coagulation properties, and has the ability to deliver radiation through light guides. However, in order to avoid carbonization of tissue, the power density must not exceed a value of between 5-10 Watts per square cm.
The power at the end of a bare light guide can be dispersed by employing the apparatus disclosed in U.S. Pat. No. 4,878,725 to Hessel et. al. titled "Apparatus for the Circumferential Irradiation of Objects". Hessel et. al. shows a diffusing light guide having a clear glass cap placed at the end of a fiber for diffusing light transmitted through the fiber. However, Hessel does not disclose how to use the diffusing light guide for treating BHP.
An object of the invention is to provide improved treatment arrangement and process for treating benign prostatic hyperplasia.
According to the present invention, a diffusing light guide into a prostate lobe and providing laser method of treating benign prostatic hyperplasia comprises the steps of inserting a power to the diffusing light guide in order to necrose and shrink surrounding tissue.
In exemplary preferred embodiments of the invention, the diffusing light guide is inserted into the central or lateral prostate lobes by inserting a trocar needle and a trocar sheath transperineally into the lobe, removing the trocar needle, inserting the diffusing light guide into the trocar sheath, and monitoring the position of the trocar needle, trocar sheath, and diffusing light guide using ultrasound.
In exemplary preferred embodiments of the invention, the diffusing light guide is inserted into the central or lateral prostate lobes transuretherally and positioned with the aid of an urethroscope.
In exemplary preferred embodiments of the invention, the diffusing light guide is an ITT (interstitial thermal therapy) light guide having a cap with a diameter between 1 and 3 mm and a length of between 10 to 30 mm.
In exemplary preferred embodiments of the invention, the diffusing light guide has cap with a diameter of 1.9 mm and a length and an active length of 20 mm and 15 mm, respectively.
Using the diffusing light guide to necrose prostrate tissue eliminates the need for surgical treatment and for the other treatments discussed above. Using a diffusing light guide instead of a bare light guide eliminates the carbonization problem associated with bare light guides.
Other advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.